Body conformation of Santa Inês, Texel and Suffolk ewes raised in the Brazilian Pantanal

Abstract

Brazilian Pantanal has edaphoclimatic adversities that can strongly affect genotypes. Therefore, sheep breeders should choose animals with a suitable body conformation able to express all the genetic potential. The objective of this work is to describe the body conformation of Santa Inês, Texel and Suffolk ewes raised in the Pantanal region. Four hundred and three adult ewes belonging to the Santa Inês (n = 188), Texel (n = 150) and Suffolk (n = 65) breeds were assessed to obtain eleven measures of length, width, and body perimeters. In addition, the morphometric measures were combined for calculations of conformation indices, milk and meat potential production, and genetic capabilities. Measurements of udder, direction of teats and ears, ear size, and head profile were also evaluated. Breed differences for quantitative variables were evaluated through analysis of variance (ANOVA) while the chi-squared test was conducted for qualitative variables. Subsequently, a factorial analysis was performed on the quantitative variables. Factors were labeled according to the factorial weights of the variables in each factor and used as new variables. The hypothesis of equality between breeds was tested simultaneously considering the new variables through multivariate analysis of variance (MANOVA) and Fischer’s discriminant function. The degree of similarity between breeds was evaluated by using canonical analysis and cluster analysis considering the mean Euclidean distance with grouping by means of complete linkage. According to the qualitative results, Texel and Suffolk ewes did not show phenotypic variability, but a well-defined breed standard. Santa Inês ewes presented variability, thus requiring genetic improvement and breed standardization. Quantitative characteristics (morphometry and indices) varied according to breed of origin. Suffolk and Texel ewes presented the most desirable model for meat production. The main difference between breeds is on body size and structure, which is relevant to the production system used in the Pantanal region.